Options for roofing underlayment for lower sloped roof

joenorm | Posted in General Questions on April 6, 2019 02:19pm

I’m guessing with a lower slope and standing seam metal planned, one would want a little more robust underlayment than heavy tar paper.

What are good options for this? Something self adhered?

thanks

Answer

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Balazs_F | Apr 06, 2019 03:05pm | #1
I am not an expert of building materials so please double check - Solitex Mento 1000 from ProClima appears to be a good fit for this application. the 3000 even includes self-adhesive strips. not cheap!
thrifttrust | Apr 06, 2019 03:40pm | #2
I usually see high temperature underlayment recommended for metal roofs. I used Hydraguard Dual Pro High Temperature Ice & Water Barrier from Menards. https://www.menards.com/main/building-materials/roofing-soffits-gutters/roofing-underlayment/building-materials/roofing-soffits-gutters/roofing-underlayment/hydraguard-dual-pro-high-temperature-ice-water-barrier-39-3-8-x-61-200-sq-ft/1511833/p-1464866315609-c-13250.htm?tid=-5369144774740139514&ipos=6

It's fully adhered and has a non-woven fabric surface to act as a slip sheet. At $.45/sq.ft. it seems reasonable.
Expert Member

Peter Yost | Apr 08, 2019 09:31am | #3
Hi Joe -

I would consider the vapor permeability of the roofing underlayment and whether or not your roof assembly is vented, and/or needs to having drying potential to the interior.

Peter
Zdesign | Apr 08, 2019 11:31am | #4
Rhino Roof U20 is probably your most cost effective underlayment. Under 4/12 pitch requires 2 layers but is a lot lighter than 30# felt and a lot stronger.
Stockwell | Apr 08, 2019 03:00pm | #5
High Temp ice and water shield--whatever the brand. I just did my 2:12 roof and that is what was spec'd